1. Field of the Invention
The present invention relates to an ink-jet head that discharges a desired liquid by supplying the liquid with energy from the outside, and a method for manufacturing the same.
2. Description of the Related Art
An ink-jet recording method is known in which the generation of a bubble is urged by supplying ink with energy, such as heat or the like, the ink is discharged from a discharging port utilizing a change in the volume of the ink, and an image is formed by causing the ink to adhere onto a recording medium. In the ink-jet recording method, side-shooter-type ink-jet heads in which ink is discharged perpendicularly to a substrate are known as one type of ink-jet heads.
As for the side-shooter-type ink-jet head, Japanese Patent Application Laid-Open (Kokai) No. 4-10940 (1992) discloses a configuration in which, in order to supply discharge-pressure generation elements on a surface of a substrate with ink from the back of the substrate, an ink supply port threaded through a single-crystal Si substrate is formed according to anisotropic etching.
In conventional side-shooter-type ink-jet heads, an ink supply port is formed from the back of a substrate according to anisotropic etching that utilizes the fact that the etching speed differs depending on the orientation of a crystal face of single-crystal Si. Accordingly, the substrate is limited to a single-crystal Si substrate, and the size of a manufactured ink-jet head is limited by the size of the single-crystal Si substrate. Another problem is that a large amount of time, i.e., 7-16 hours, is required for performing anisotropic etching of Si.
The inventor of the present invention has proposed, in Japanese Patent Application Laid-Open (Kokai) No. 1-49662 (1989), a technique in which compatibility of excellent heat conduction and a low cost is realized by using alumina as a substrate material other than silicon, and depositing silicon on an alumina substrate.
It is considered that, by using such a substrate, reduction in the production cost and the processing time is realized. However, when forming a threaded hole using the substrate disclosed in Japanese Patent Application Laid-Open (Kokai) No. 1-49662 (1989), a silicon layer sometimes peels at portions surrounding the threaded hole.